[llvm-branch-commits] [DirectX] Revert specialized createOp methods part of #101250 (PR #104245)

[Justin Bogner via llvm-branch-commits]

https://github.com/bogner created https://github.com/llvm/llvm-project/pull/104245

In 8cf85653b6f5 "[DirectX] Make DXILOpBuilder's API more useable" we introduced
specialized createOp methods for each DirectX op for convenience, but the API
is buggy and untested. It also isn't actually as useful as I imagined it would
be since we don't have argument names or const-ness represented in DXIL.td
currently. Remove these methods for now and we can reintroduce them if we
actually need them later.